反应详情

A mixture of 2-trifluoromethylbenzamidine (1.12 g, 5 mmol), sodium ethoxide (1.02 g, 15 mmol) and 4,4-dimethyl-3-oxo-pentanoic acid methyl ester (0.80 mL, 5 mmol) in ethanol (50 mL) and was heated at reflux for 16 hours. The reaction was cooled, concentrated, diluted with water and acidified with 2 N hydrochloric acid. This solution was extracted with ethyl acetate, dried over sodium sulfate and concentrated. Purification by flash chromatography [SiO2, methanol:dichloromethane (2:98)] provided the title compound (0.48 g, 32% yield) as a yellow solid; 1H-NMR (500 MHz, DMSO-d6) δ12.8 (br s, 1H), 7.89 (d, J=7.5 Hz, 1H), 7.78 (m, 2H), 7.71 (d, J=7.4 Hz, 1H), 6.24 (s, 1H), 1.20 (s, 9H) ppm; LC-MS 297.03 (M+H); Rt (Method A) 3.30 minutes.

1. temperaturewas heated
2. temperatureat reflux for 16 hours
3. temperatureThe reaction was cooled
4. concentrationconcentrated
5. additiondiluted with water
6. extractionThis solution was extracted with ethyl acetate
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated
9. customPurification by flash chromatography [SiO2, methanol:dichloromethane (2:98)]